Well, one thing was dead sure, and that was that Tom Sawyer was in earnest, and was actuly going to help steal that nigger out of slavery.

Then the preacher begun to preach, and begun in earnest, too; and went weaving first to one side of the platform and then the other, and then a-leaning down over the front of it, with his arms and his body going all the time, and shouting his words out with all his might; and every now and then he would hold up his Bible and spread it open, and kind of pass it around this way and that, shouting, "It’s the brazen serpent in the wilderness!

There are no more uses of "earnest" in the book.

Show samples from other sources

Both sides were deeply in earnest, even passionate.

She has a casual, go-with-the-flow personality and doesn’t appreciate his earnestness.